Refillable multiple fuse units



Sept. 25, 1934. w.. A. STARCK 1,974,694

REFILLABLE MULTIPLE FUSE UNIT Filed May 27, 1932 Patented Sept. 25, 1934 UNITED srATss rce This invention relates to fuses and has for an object to provide a refillable multiple :fuse unit having .a wheel type fuse providing six fuses, more or less, which when blown one at a time, may be i readily removed and the fuse unit replenished with anew wheel type fuse.

A further object is to provide a .fuse :unit in which positive contact of the circuit connections may be made by simply drawing the cap down on the body of the unit by a single center screw.

A further object is to provide a pin in the side of the fuse zbody selectively engageable in grooves in the cap to properly position the radial arms of the fuse to make contact, and complete the circuit.

A further object is to provide a fuse unit which will not employ springs of any type whatsoever in its construction, which will provide a complete insulating housing for the wheel fuse and thus eliminate fire hazard, and which will em,-

ploy no nuts or similar devices to hold the fuse wheel inplace. i

A further object is to provide a fuse unit in which the cap may be rotated in either direction, and which will have no exposed terminals when in the fuse socket or other fixture.

With the above and other objects in view the invention consists in certain novel details of construction and combinations of parts hereinafter fully described and claimed, it being understood that various modifications may be resorted to within the scope of the appended claims without departing from the spirit or sacrificing any of the advantages of the invention,

In the accompanying drawing forming part of this specification,

Figure 1 is a side elevation of the fuse unit, Figure 2 is a front elevation of the fuse unit, Figure 3 is a longitudinal section of the fuse unit, taken on the line3-3 of Figure l,

Figure l is a front elevation of the body of the fuse unit with the cap and wheel fuse removed, Figurefi is a rear elevation of the capequipped with the wheel fuse, and v Figure 6 is a detail perspective view of the wheel fuse. .Referring now to the drawing, it will be seen that the fuse unit comprises a housing including a base 10 and a flanged cap 11 both formed of insul'ating material such as porcelain or other material. f I a The base is provided with a metal threaded ferrule 12 which constitutes the' outer circuit terminal of the fuse unit, and permits of the base being screwedintothe fuse receptacle or other fixture. The center circuit terminal 13 consists preferably of a brass socket Screw 13 which is revolubly mounted in an axial opening in the base and is provided with a-knurle'd knob l t. The screw is comparatively short so as not to reach to the "end face 15 of the base and is counterbore'd and threaded, as shown at 16. The base is also provided with a radially disposed metal pi'n 1'7 which contacts with the outer scre'w terminal 1 2 at the outer end and at the inner end 'conta'ct's with a metal .pin 18 which is embedded longitudinally in the base parallel to the screw '13 and projects through the face 15 of the base to estab lish contact between the outer terminal 12 and the hereinafter described wheel fuse. The end face 15 of the base is provided with an annular groove 19 disposed concentric with the axis of the base to receive the flames when the fuse lown.

The flange of the 'cap 11 is thickened to pro vide an annular ledge or shoulder 20 which forms a support for the outer ends 'of the radial arms 21 of a wheel fuse, designated in general by the numeral 22. The cap is provided inwardly of the shoulder with an annular series of 'substan tially triangular lugs 23 which constitute spacers to engage snugly betweenthe arms of the wheel fuse and hold the fuse in place in the cap; The wheel fuse is provided with a central opening 24 which snugly receives a brass screw 26 which is threaded into the center terminal socket screw 13 and thus the fuse is electrically connected to the center terminal. The screw 26 passes through an axial opening 2'7 formed in the end face of the base 10, which opening registers with the thread ed bore of the center terminal socket screw 13; V The screws 13 and 26 constitute an extension screw, as will be understood. The center terminal of the fuse unit consists of the extension screw 1326 which unites the cap 11 and base 10, By referring to Figure 3, it will be seen that the outer end of the screw 26 is provided with a square neck 28 of insulating material which is riveted, as shown at 29, or otherwise secured to the screw and passes through an; axial square opening 30 formed in the cap 11. The outer end ofthe neck is provided with an integral star shaped button 31 which engages the outer face of the cap.- The inner end face 32 of the neck 28 forms an-abutment which supports the center of the wheel fuse. H

For properly positioning the cap onthe base so that the pin 18 will make contact with the one of the arms 21- of the wheel fuse, recesses 33 are formed in the end edge of the flange of the cap, preferably each recess being in alignment with one of the radial arms of the wheel fuse,

as shown in Figure 5. A pin 34 is embedded in the side of the base 10 and is adapted to be selectively received in the seats or recesses 33 when there is an annular tongue 35 on the face of th'e-l base which is received in an annular groove 36. This tongue and groove connection betweenthe cap formed in the edge of theoap flange.

and the base seals the chamber 19 of the base so that when each arm of the fuse is'blownthe" flame will be confined in the chamberand posi-r tively prevented against escape from between the cap and the base.

In operation, as each arm of the fuse blows, a new usable arm may. be brought into contact with the pin 18 by first unscrewing the fuse unit bodily from the fuse receptacle. Next back out the screw 13,.to permit separation of the cap and the base sufficiently to-disengage the pin 34 from the recesses 33;: Now the cap may be rotated in the base 10 by turning the socket screw 13 by means of its knob 14, or turning the cap until the succeedingirecess. 33 registers with the pin 34. Thereupon the socket screw may be rotated, while the cap is held stationary .inth'e hand to cause the button 31 to push the cap'ahead of it untilthe pin 34= is received into said succeeding recess. .1 ,When all of the arms of the wheel fuse have been blown anew wheel fuse may be supplied by simply unscrewing the center screw 13 and removing the cap 11 bodily from the base 10. A new wheel fuse may then be slipped upon the screw 26..and the arms 21 engaged between the lugs'23'of the cap. The cap may now be replaced to bring the notch numbered 1, for instance, into registration with the stop pin 34 of the base. .The socket screw 13 is now tightened todraw the cap tight against the base and bind number one arm of the wheel fuse tightly against the pin 18.. The fuse unit maynow be screwed into its receptacle.

or covering around the wheel fuse so that fire radial arms, said'fuse being mounted on said' screw and electrically connected thereto, an outer circuit terminal carried by the base having a contact adapted to engage said arms, interfitting means between the base and the cap adapted to dispose said arms selectively in en 1,974,e94 a a gagement with said contact, means on the screw engageable with the cap for drawing the cap down tight upon the base when the screw is tightened to hold said interfitting means and said contact and said fuse in operative positions, and a tongue and groove connection between the cap and the base sealing the cap and base against escape of flame when the fuse is blown.

2. A fuse unit comprising a base, a flanged capon the -base,'a screw for slidably and rotatably mounting the cap on the base and forming a center circuit terminal, a wheel fuse removably disposed in the cap, said fuse being concentrically ;mounted on said screw and being electrically connected therewith, an outer circuit terminal carriedbythebase having a contact adapted to engage said fuse, a stop projection on the baseQand seats on-the flange of the cap adapted to selectively receive the stop projection and dispose said fuse to engage said contact.

.. 3. A fuse plug comprising abase, a cap abutting the outer end face of said base and rotatable relative thereto, the abutting faces of the cap and base having grooves formed therein and registering to define a chamber between the base and cap spaced from the outer marginal edges of the abutting faces, the cap being also formed with radial grooves intersecting-the first mentioned. groove, a center contact, a side contact carried by said base, a fuse disk abutting the center contactbetween the cap and base and havingv radial arms seated in the radiating grooves ofthe cap and extending transversely through the chamber with their ends terminating in position to successively engage the side contact when the cap is'rotated,-and means for forming a sealed joint between marginal portions of the abutting faces of the cap and base to confine flame in thechamber 'when'an arm of the fuse disk is burned, i g

. 4. A fuse plug comprising abase, a cap abutting the outer end face of said base, a fastener extending axially through the base and cap and constituting a center contact detachably and rotatably connecting the base and cap, the abutting faces being formed with registering annular grooves spaced from the fastener and outer marginal edges of the faces and defining a chamber between the faces, aside contact carried by the 4 base and exposed through the outer face thereof between the groove and marginal edge of the base, and a fuse disk mounted about said fastener between the base and cap to turn with the cap and having-radial arms extending across the chamber and terminating in position to successively engage the side contact when the cap is rotated, means being provided to form a sealed joint between marginal portions of the abutting faces of the cap and base toconfine flame in the chamber when an arm of the fuse disk is burned. V 5. 'A'fuse plug comprising a base, a cap fitting the-outer end of said baseandrotatable relative thereto,a-center'contact, the opposed faces of the cap and base being grooved to defin'e an annular chamber spaced fromthe center'contact and outer margins of the base and cap respectively, a side contact, and a'fuse between thecap and base about thecenter contact turning with the cap and having radial arms extending transversely through the chamber in spaced relation to inner and outer walls thereof and having their outer ends disposed to successively engage the side contact when the cap is rotated, and means to form a sealed joint between marginal portions of the abutting faces of the cap and base to confine flame in the chamber when an arm of the fuse is burned.

WILLIAM A. STARCK. [L.S.] 

